1. Field of the Invention
The present invention relates to a shift position detecting device that includes a plurality of projection rows each of which includes projecting portions arranged at a plurality of places in a spaced-apart manner in the circumferential direction of a shift drum constituting a part of a multi-stage transmission having gear trains of a plurality of shift stages that are selectively establishable, and are mounted on the shift drum. Three switches that are fixedly arranged at least one by one corresponding to the plurality of projection rows such that a switching mode is changed from an OFF state to an ON state by being brought into contact with the projecting portions. A shift position determining means that determines a shift position by collating the shift position allocated to the detection logic based on the detection logic that is formed of “1” generated when the switches are in an ON state and “0” generated when the switches are in an OFF state, wherein “1, 1, 1” is allocated as the detection logic at a neutral position arranged between a first speed position and a second speed position.
2. Description of Background Art
JP-A-2011-196517 discloses a shift position detecting device where a plurality of projection rows each of which has projecting portions at a plurality of places in a spaced-apart manner in the circumferential direction of a shift drum are formed on the shift drum. A present shift position is detected by a combination of the turning ON and OFF of three switches where a switching mode is changed from an OFF state to an ON state by being brought into contact with the projecting portions of the projection rows. In this shift position detecting device, a state where all three switches are turned on is allocated to a neutral position.
Friction is increased at a moment when the switch is brought into contact with the projecting portion of the projection row of the shift drum. However, when timings at which the plurality of switches come into contact with the projecting portions are equal, a friction caused by the contact of the switch to the projecting portion occurs simultaneously with respect to the plurality of the switches. Thus, the movement of the shift drum is liable to be obstructed. More particularly, in the shift position detecting device disclosed in the above-mentioned JP-A-2011-196517 where the state in which all three switches are turned on is allocated to a neutral position, when a shift position is changed to the neutral position from the first speed position or the second speed position, there is a high possibility that the plurality of switches are brought into contact with the projecting portions simultaneously whereby a friction is liable to be increased and, at the same time, when the neutral position is arranged between the first speed position and the second speed position, it is often the case that an operator performs a shift operational toward a neutral position side with a force smaller than a force that he uses in a usual operational. Thus, the operator is liable to easily perceive the influence of a friction. In view of the above, there has been a demand for the reduction of a friction at the time of changing a shift position to a neutral position.